Means for controlling the operation of material conveying devices



Oct. 6, 1959 L. G. CALDWELL 2,907,606

. MEANS FOR CONTROLLING THE OPERATION OF MATERIAL CONVEYING DEVICES Filed Sept. 4, 1957 4 Sheets-Sheet'l INVENTOR.

LG. CALDWELL ATTORN Oct. 6, 1959 Filed Sept. 4, 1957 FE-1TB.

L. G. CALDWELL MEANS FOR CONTROLLING THE OPERATION OF MATERIAL CONVEYING DEVICES 4 Sheets-Sheet 2 INVENTOR.

" L. G. CALDWELL BYWWQVJW ATTORNEY Oct. 6, 1959 1.. G. CALDWELL 2,907,606

MEANS FOR CONTROLLING THE OPERATION OF MATERIAL CONVEYING DEVICES Filed Sept. 4, 1957 4 Sheets-Sheet 3 INVENTOR.

L. G. CALDWELL ATTO R N EY 1959 L. G. CALDWELL 2,907,606

MEANS FOR CONTROLLING THE OPERATION OF MATERIAL CONVEYING DEVICES Filed Sept. 4, 1957 4 Sheets-Sheet 4 ii 755 X T 5 [ii I 5% v [72 Asa "j)/ Ff 6? 5 1/ g T K67 7& 7/-

K- f L 43 24 7 76 M (42 INVENTOR. Le. CALDWE LL BY JIM-1%,

ATTORNEY United States Patent MEANS FOR CONTROLLING THE OPERATION OF MATERIAL IONVEYING DEVICES Application September 4, 1957 Serial No. 682,022

Claims. (Cl. 302-53) This invention relates to means for controlling the operation of material conveying devices, such as a pneumatic pump, consisting of a resiliently supported container for the material having a material inlet and outlet, a fluid pressure inlet connected to a source of fluid pressure to discharge material from the container through the material outlet, a gate to control the feed of material into the material inlet, a closure member to pressure seal the material inlet, a valve to control the fluid pressure inlet, and pressure operative means operatively connected to said gate, closure member and fluid pressure inlet valve and actuated by the fluid pressure to operate the gate, closure member and fluid pressure inlet valve.

It is an object of the invention to provide an electrical circuit having interconnected component parts whereby the movement of the container caused by a predetermined quantity or weight of the material in the container initiates the operating cycle of the material conveying device and the fluid pressure involved in the fluid pressure conveying operation continuing and ending the operating cycle.

It is another object of the invention to arrange the component parts of the electrical circuit whereby the operating cycle will continue after initiation of said cycle irrespective of the movement of the container.

Other objects and advantages of the invention will be described hereinafter.

In the drawings accompanying and forming a part of this application:

Figure 1 is a perspective view of a material conveying device having the invention embodied therein;

Figure 2 is a vertical sectional view of the material conveying device with the supporting structure removed and operating means diagrammatically shown and the material and fluid pressure control means of the device being shown in a position when the device is not in operation;

Figure 3 isa view similar to Figure 2 with the operating means omitted and the material and fluid pressure control means of the device shown in initial position to feed material into the device;

Figure 4 is a view similar to Figure 3 with the material and fluid pressure control means of the device shown in position to stop the feed of material into the device, to

pressure seal the device and to discharge the material from the device by fluid pressure;

Figure 5 is a view similar to Figures 3 and 4 with the -material and fluid pressure control means in the position as a pneumatic pump, consisting of a rigid walled container 7 resiliently supported in a structural steel frame 8 by springs 9 having the lower endsmounted on brackets 10 secured to the frame 8 and the upper ends engaging brackets 11 secured to the exterior of the container 7.

Thecontainer 7 is maintained in vertical position by rollers 11 rotatably supported in the brackets 10 to engage Patented Oct. 6, 1959 diametrically opposed portions of the container. The container 7 is arranged at the top with a material inlet 12 into which a discharge spout 13 of a material hopper 14 is extended. The connection between the container inlet 12 and the hopper spout 13 is sealed by a. flexible sleeve 15 attached at the opposite ends to the container inlet 12 and the hopper spout 13 and which permits vertical movement of the container. The container 7 has a conical or hopper bottom 16 terminating in a material outlet 17 arranged with a laterally extending discharge neck 18 connected to a material transporting conduit 19.

The feed of the material through the hopper spout 13 is controlled by a gate 20 adjustably mounted at its center portion by a shaft 21 fixed to the gate and pivoted in the spout 13. The gate 20 is actuated to open and close positions by fluid pressure operative means consisting of a cylinder 22 supported by the frame 8 and a. piston 23 slidable in the cylinder 22 and having a rod 24 extending from one end of the cylinder 22 and the extended end pivotally connected to one end of an arm 25 having the opposite end fixed to the shaft 21 of the gate 20, as shown in Figure 2. The opposite end portions of the cylinder 22 are connected by fluid pressure pipes 26 and 27 to a fluid pressure supply conduit 28 through a branch pipe 2 connected to said conduit 28 and having a lateral extension 30 connected to a four-way fluid pressure valve 31 of conventional construction. The fluid pressure pipes 26 and 27 are connected to the valve 31 in such a manner that when the valve 31 is actuated to permit the fluid pressure to flow to the pipe 27 and the residual fluid pressure in the left hand end portion of the cylinder 22 is led to the atmosphere or fluid reservoir through exhaust conduit 30', the flow of fluid pressure to the pipe 26 is shut-off, whereby the piston 23 is moved tothe left hand end portion of the cylinder 22 and the gate 24) is actuated to shut-ofl the flow of material from the hopper 14 to the container 7, as shown in Figures 2 and 4. When the valve 31 is actuated to open communication between the pipe 26 and the supply conduit 28 and close the communication between the pipe 27 and the supply conduit 28, the fluid pressure in the right hand end portion of the cylinder 22 is exhausted to the atmosphere or fluid pressure reservoir through an exhaust conduit 30' 20 to open position, as shown in Figures 3. and 5. The

valve 31 is actuated by an electromagnet 32, as shown in Figure 6. Energizing of the electromagnet 32 will actuate the valve 31 to connect the pipe 27 to the conduit 28 and shut-off the pipe 26 from the conduit 28, and the deenergizing of the electromagnet 32 will permit the valve 31 to shut'ofl the pipe 27 from the conduit 28 and connect the pipe 26 to the conduit 28. When either end portion of the cylinder 21 is shut-off from the fluid pressure supply, the residual fluid pressure in said shut-off end portion is led to the atmosphere or a fluid pressure reservoir through the exhaust conduit 30. The electric circuit in which the electromagnet 32 is connected will be de' scribed hereinafter.

When the container 7 is filled with a predetermined quantity or weight of material, the gate 20 is closed as described hereinbefore and subsequently the material inlet 12 is pressure sealed by a closure member 33 pivotally supported in the container 7 by a shaft 34 fixed to an arm 35 of the closure member 33 and rotatably supported in the inlet portion of the container 7'. The closure member 33 is adapted to engage a sealing ring 36 mounted in the material inlet 12, as shown in Figure 4. The closure member 33 is actuated by fluid pressure operative mean similar to the fluid pressure operative means 22, 23 and comprising a cylinder 37 supported by the frame 8 and a piston 38 slidable in the cylinder 37 and having a rod 39 extending from one end of the .by the closing movement of the gate 20 and the energizing of the electromagnet 43 will actuate the valve 42 to connect the pipe 40' with the conduit 28 and shut-01f the pipe 41 from the conduit 28, whereby the piston 38 will be moved to the right hand end portion of the cylinder 37 and the closure member 33 will be actuated to engage the sealing ring 36 and pressure seal the material inlet 12. De-energizing the electromagnet 43 will permit the valve 42 to close the communication between I the pipe 40 and the conduit 28 and open the communication between the pipe 41 and the conduit 28 which will move the piston 38 to the position shown in Figure 2 and actuate the closure member 33 to open position, as shown in Figures 2, 3 and 5. The circuit in which the electromagnet 43 is connected will be described hereinafter, The fluid pressure in the pipe 41 is controlled by a pressure regulator 44, as shown in Figure 2. When either end portion of the cylinder 37 is shut-off from the fluid pressure supply, the residual fluid pressure in said shut-off end portion is led to the atmosphere or a fluid pressure reservoir through an exhaust conduit 29'.

After the gate 20 and the closure member 33 are closed, as shown in Figure 4, the fluid pressure is permitted to flow from the supply conduit 28 to a plurality of nozzles 45 arranged in any desired manner in the material outlet 17 to aerate and discharge the material in a fluid stream from the container '7 through the discharge neck 18 and the transporting conduit 19. The flow of fluid pressure from the supply conduit 28 to the nozzles 45 is controlled by a valve 46 in an extension 47 of the conduit 28, as shown in Figures 1 and 2. The valve 46 is actuated by fluid pressure operative means comprising a cylinder 48 supported by the frame 8 and a piston 49 slidable in the cylinder 48 and having a rod 50 extending from one end of the cylinder 48 and pivotally connected to an arm 51 secured to the valve '46, as shown in Figures 1 and 2. The pipe 40' is con- 'end portion of the cylinder 48 from the fluid pressure supply conduit 28 and open the left hand end portion of the cylinder 48 to the conduit 28, whereby the piston 49 is moved to the position shown in Figure 2 with the valve closed. When either end portion of the cylinder 48 is shut-01f from the fluid pressure supply, the residual fluid pressure in said shut-off end portion is led to the atmosphere or a fluid pressure reservoir through the exhaust conduit 29'.

Excessive fluid pressure in the container 7 is released through a vent. 52 arranged in the material inlet 12 and communicating with a space between said inlet 12 and the hopper spout 13 and above the sealing ring 36, so that the excessive fluid pressure is released from the container 7 after the container has. completed a discharge Cycle, as shown in Figure 2, during the feeding of the material into the container, as shown in Figure 3, or when the container is in condition to receive the material from the hopper 14 but the hopper is empty, as shown in Figure 5. When fluid pressure is req i ed to di c a g the material from the container 7, the vent 52 is shutoff from the interior of the container by the closure member 33 engaging the sealing ring 36, as shown in Figure 4.

The hereinbefore described structure and operation is old in the art as shown in Patent No. 2,032,367 patented March 3, 1936, to Joseph E. Kennedy and Herbert W. Johnson, except that the fluid pressure operative means 22-23, 37-48 and 4849 were not controlled by the magnetic operative valves 3132 and 4243.

The present invention relates to the de-energizing of the magnetic operative valve 3ll-32 and the energizing of the magnetic operative valve 42-43 by the movement of the container 7 caused by a predetermined quantity or weight of the material in the container and maintaining the magnetic operative valves 31-32 and 4243 in said de-energized and energized conditions, respectively, by the fluid pressure in the container. This is accomplished by an electric circuit and component electric devices mainlyillustrated in Figure 6, and comprising the electromagnets 32 and 43 connected by a conductor 53 to one side of a source of electricity 54 through a manually operative main switch 55. The electromagnet 32 is connected to the other side of the source of electricity 54 through normally closed contacts 56 of a single contact magnetic switch having an electromagnet 57 and through a manually operative selector switch 58 which is manually actuated to closed position when it is desired to place the device in operation after the manually operative main switch 55 has been closed. The manually operative'selector switch 58 is connected to said other side of the source of electricity 54 by a conductor 59. The manual closing of the selector switch 58 will energize the electromagnet 32 and actuate the fourway valve 31 to open the gate 20 in the manner described hereinbefore and shown in Figures 3 and 5.

The electromagnet 43 is connected to the conductor 59 by electric devices which are actuated to circuit closing position by the movement of the container 7 caused by a predetermined quantity or weight of the material in said container. One of said devices is a loadswitch 60 having an arm 61 extending into the path of travel of an abutment 62 fixed to the container 7. The abutment 62 will engage and move the arm 61 to close the switch 60 when the container 7 contains a predetermined quantity or weight of material. One side of the switch 60 is connected to'the conductor 59, as shown in Figure 6.

The circuit of the load-switch 60 is completed through normally closed contacts 63 of a double contact fluid pressure sensitive switch 64 operative by the fluid pressure in the container 7 through a conduit 65, Figure 2, communicating with the upper interior portion of said container. The contacts 63 are normally in circuit closing position when there is no fluid pressure in the container 7. The contacts 63 are connected to the conductor 53 through conductors 66 and 67 and an electromagnet 68 of a double contact magnetic switch having pairs of normally open contacts 69 and 70 connected at one side to the conductor 59, as shown in Figure 6.

The closing of the load-switch 60 will energize the electromagnet 68 through the normally closed contacts 63 and simultaneously close the contacts 69 and 70. The closing of the contacts 69 will maintain the circuit even though the load-switch 60 is momentarily opened by the bouncing or fluctuating movement of the container 7.

The other side of the contacts 70 is connected to the conductor 53 through a conductor 71, electromagnet 57 and conductor 72, whereby the closing of the contacts 70 will energize the electromagnet 57 to open the circuit through the contacts 56 thereby de-energizing the electromagnet 32 and permitting the four-way fluid pressure valve 31 to be actuated so that the flow of fluid pressure will be to the right hand end portion of the cylinder 23, looking at Figure 2, close the hopper spout 13.

"The actuation of the gate 20 to close position will close a limit switch 73 by an arm 74 of said switch extending into the path of travel of the rod 24 of the piston 23 in the cylinder 22, whereby in the movement of the rod 24 in a left hand direction, looking at Figure 2, the rod 24 will engage and move the arm 74 to close the limit switch 73. The limit switch 73 is connected to the contacts 70 through a conductor 75 and to the electromagnet 43 through a conductor 76, whereby the closing of the limit switch 73 will energize the electromagnet 43 which will actuate the four-way fluid pressure valve 42 to direct the flow of fluid pressure to the left hand end portion of the cylinder 37 and to the right hand end portion of the cylinder 48 thereby moving the closure member 33 to pressure sealing position and the fluid pressure inlet valve 46 to open position permitting the flow of fluid pressure from the supply conduit 28 to the nozzles 45.

With the interior of the container 7 fluid pressure sealed by the closure member 33 and the fluid pressure entering said container through the nozzles 45, the material is discharged from the container through the discharge neck 18 and the transporting conduit 19. As the discharge of material progresses, fluid pressure is built up in the container 7 to actuate the fluid presure sensitive switch 64 tp fopenahe circuit through the normally closed contacts 63 and close thecircuit through contacts 77 of said to actuate the gate20 to,

fluid pressure sensitive switch. The contacts 77 are coni nected to the conductor 59 through a conductor 78 and the contacts 70 of the double contact magnetic switch through a conductor 79 connected to a terminal of the conductor 71arrd to an intermediate portion of the conductor. 75, as shown in Figure 6. The closing of the contacts 77 will transfer the circuit of the electromagnet 57 from the contacts 70 to the contacts 77 through the conductors 59 and '78, contacts 77, conductors 79 and 71, electromagnet 57 and conductors 72 and 53. The contacts 77 in circuit closing position will maintain the electromagnet 43 in energized condition so that the closure member 33 will remain in fluid pressure sealing position and the fluid pressure flowing to the nozzles 45 as long as there is sufficient fluid pressure in the container 7 to operate the fluid pressure sensitive switch 64 to open the contacts 63 and close the contacts 77.

As the discharge of the material through the discharge neck 18 and the transporting conduit 19 continues, the container 7 will be moved upwardly by the springs 9 to disengage the abutment 62 from the arm 61 and permit the load-switch 69 to assume its circuit opening position, but the material will continue to be discharged from the container 7 due to the fluid pressure in said container actuating the fluid pressure sensitive switch 64 to maintain the contacts 63 in circuit opening position and the contacts 77 in circuit closing position.

Finally the material is completely discharged from the container 7 and the fluid pressure in said container decreases causing the fluid pressure sensitive switch 64 to assume its initial position with the contacts 63 in circuit closing position and the contacts 77 in circuit opening position. When the fluid pressure sensitive switch 64 assumes its initial position, the electromagnet 57 is de-energized and the contacts 56 assume theircircuit closing position whereby the electromagnet 32 is energized to actuate the four-way fluid pressure valve 31 to open the gate 20 and permit feeding of the material into the container 7, as shown in Figures 3 and 5. Concurrent with the opening of the gate 20, the closure member and the' eiha-i side of said switch connected to th e normally closed contacts 63 ofthe fluid pressure sensitive switch 64 through conductor 81. The push button switch is manually actuated to circuit closing position when it is desired to operate the device for testing purposes or to clean out a partial load of material from the container. The closing of the push button switch 80 will energize the electromagnet 68 through the contacts 63 thereby closing the contacts 69, 70, energizing the electromagnet 57 to actuate the four-way fluid pressure valve 31 to close the gate 20. The closing of the gate 20 will close the limit switch 73 and energize the electromagnet .43

to close the closure member 33 and open the fluid pressure inlet valve 46. Thepush button switch 80 takes the place of the load-switch 60 and permits the comrnencement of a material discharge cycle manually instead of by the movement of the container 7.

In Figure 2, the electric circuit components, such as the single contact magnetic switch 56, 57 and the double contact magnetic switch 637 are housed in a casing 82 mounted on the frame 8, as shown in Figure 1. Theselector switch 58 and the push button switch 80 are arranged in a box 83 also mounted on the frame 8, as shown in Figure 1. The main line switch 55 may be located in the casing 82. In Figure 2, the casing 82 and the box 83 are shown together to simplify the diagram matic showing in said figure.

Having thus described my invention I claim:

1. In means for controlling the .operation of material conveying devices including a resiliently supported container for the material having a material inlet and outlet, a fluid pressure inlet connected with a source of fluid pressure to discharge material from the container through the material outlet, a gate to control the feed of material into the material inlet, a closure member to pressure seal the material inlet, a valve to control the fluid pressure inlet, and fluid pressure operative means operatively connected to said gate, closure member andfluid pressure inlet valve and actuated by the fluid pressure to operate the gate, closure member and fluid pressure inlet valve, the improvement comprising an electric circuit including magnetic operative valves having electromagnets directly connected to one side of a source of electricity and valves controlling the flow of fluid pressure to the pressure operative means and maintaining the flow of fluid pressure to the fluid pressure operative means whereby the gate and closure member are actuated to open position and the fluid pressure inlet valve is actuated to shut-off the fluid pressure from the container when the container is empty or contains a fluid pressure below a predetermined value, a load-switch directly connected to the side of the source of electricity opposite the side connected to the electromagnets of the magnetic operative valves and actuated to circuit closing position by movement of the container caused by a predetermined quantity of material in the container, a double contact fluid pressure sensitive switch having a pair of contacts normally in circuit closing position and actuated to circuit opening position by fluid pressure in the container and a pair of contacts normally in circuit opening position and actuated to circuit closing position by fluid pressure in the container, the normally circuit closing contacts of the double contact pressure sensitive switch being connected to the load switch, a double contact magnetic switch energized by the normally circuit closing contacts of the double contact pressure sensitive switch when the load-switch has been actuated to circuit closing position and said double contact magnetic switch having a pair of contacts connected parallelly of the load-switch to main-tain a circuit around the load-switch when the load-switch is intermittently actuated to open position by a bouncing movement of the container, a single contact magnetic switch normally energizing the electromagnet of the magnetic operative valve controlling the fluid pressure operative means for the gate and actuated to circuit opening position by the closing of'the second pair of contacts of the doublecontact magnetic switch to close the gate, and a limit switch actuated to circuit closing position by the closing movement of the gate and connected to the circuit of the electromagnet of the magnetic operative valve controlling the fluid pressure operative means for the closure member and the fluid'pressure inlet valve to close said circuit and cause the actuation of the closure member to pressure sealing position and open the fluid pressure inlet valve to inject fluid pressure into the container and connected in the circuit of the second pair of contacts of the double contact magnetic switch to complete the circuit of said limit switch.

2. Means for controlling the operation of material conveying devices as claimed in claim 1, wherein a push button switch is directly connected to the side of the source of electricity connected to the load-switch and directly connected to the normaly closed contacts of the pressure sensitive switch for testing or to clean out a partial load of material from the container. 1

3. In means for controlling the operation of material conveying devices as claimed in claim 1, a selector switch directly connected to the side of the source of electricity directly connected to the load-switch and connected to the single contact magnetic switch to energize the electromagnet of the magnetic operative valve of the fluid pressure operative means for the gate to actuate the gate to open position and commerce fillingthe container.

4. Means for controlling the operation of material conyeying devices as claimed in claim 1, wherein the gate, closure member and fluid pressure inlet valve are connected to individual fluid pressure operative means, there are two magnetic operative valves, the fluid pressure operative means connected to the gate is controlled by one of the magnetic operative valves, and the fluid pressure operative means connected to the closure member and the fluid pressure inlet valve are controlled by the other magnetic operative valve.

5.- In means for controlling the operation of material conveying devices including a resiliently supportedcontainer for the material'having a material inletand outlet, a fluid pressure inlet connected with a source :of fluid pressure to discharge material from the containerthrough the material outlet, a gate to control the feed of material into the material inlet, a closure member to pressure seal the material inlet, a valve to control the fluid pressure inlet, and fluid pressure operative means operatively connected to said gate, closure member andfluid pressure inlet valve and actuated by the fluid pressure to operate the gate, closure member and fluid pressure inlet valve, the improvement comprising electric operative means to actuate the pressure operative means connected to the gate normally active to actuate the gate to open position and inactivated by movement of the container caused by a predetermined quantity of material in the container to close the gate, a second electric operative means to actuate the fluid pressure operative means connected to the closure member and the fluid pressure inlet valve normally inactive and actuating the closure member to open position and actuating the fluid pressure inlet valve to close position and activated by the closing movement of the gate to close the closure member and open the fluid pressure inlet valve, and a third electric operative means activated by the fluid pressure in the container to maintain the first electric operative means in inactive condition and the second electric operative means in active condition.

References Cited in the file of this patent V UNITED STATES PATENTS 

